1. Field of the Invention
The present invention relates to an endoscopic observation apparatus and a medical device holder used in the medical field, for example, neurosurgery, by inserting an endoscope into a body cavity.
2. Description of the Related Art
Generally, medical instruments such as an endoscope and treatment tool are sometimes used in being held by a holder. For example, Jpn. Pat. Appln. KOKAI Publication No. 8-52158 (patent document 1) discloses an articulated holder arm which can hold medical instruments such as an endoscope and treatment tool. This holder arm has a plurality of arms, a joint between the arms, and a brake means to switch the joint to a fixed state and a released movable state. A grip is provided at the front end of the holder. The grip holds and fixes the outer circumference of medical instruments such as an endoscope and treatment tool. When the brake means is switched to the released state, each arm of the multi-joint arm structure becomes movable in three dimensions. Thus, the medical instrument motion is adjusted in three dimensions through the holder. By switching the brake means to the fixed position in the state that the instrument is being inserted into a desired part, each arm is fixed at its moved position.
Further, Jpn. Pat. Appln. KOKAI Publication No. 9-149877 (patent document 2) discloses an endoscope holder to hold an endoscope. The endoscope disclosed here has a thick part connected to the base end of a slender insertion part which is inserted into the tube cavity. In the endoscope holder of the patent document 2, an endoscope attachment is provided at the front end of the endoscope holder which is movable in three dimensions. This attachment has a substantially cylindrical insertion hole to insert the insertion part of the endoscope, and an endoscope fixing screw. The insertion hole is shaped to meet the outside shape of the thick part of the endoscope. The endoscope holder is constructed to press and fix the endoscope to the attachment by tightening the fixing screw after the thick part is inserted into the insertion hole of the attachment.
Further, Jpn. Pat. Appln. KOKAI Publication No. 8-206059 (patent document 3) discloses an endoscope holder with the structure different from the unit of the patent document 2. This endoscope holder contains an image pickup optics to pick up an image observed through an endoscope, and a variable magnification optics to change the magnification of a pickup image. An attachment provided at the rear end of the endoscope is connected removably to the front end of the holder. The holder is further provided with an endoscope attachment, which is attached optically removably to the optics of the endoscope. At the front end of the holder, a plurality of controls are arranged to adjust and change the direction, magnification and focal position of an observation image.